title: Novel two stage bio-oxidation and chlorination process for high strength hazardous coal carbonization effluent.
abstract: Effluent generated from coal carbonization to coke was characterized with high organic content, phenols, ammonium nitrogen, and cyanides. A full scale effluent treatment plant (ETP) working on the principle of single stage carbon-nitrogen bio-oxidation process (SSCNBP) revealed competition between heterotrophic and autotrophic bacteria in the bio-degradation and nitrification process. The effluent was pretreated in a stripper and further combined with other streams to treat in the SSCNBP. Laboratory studies were carried on process and stripped effluents in a bench scale model of ammonia stripper and a two stage bio-oxidation process. The free ammonia removal efficiency of stripper was in the range 70-89%. Bench scale studies of the two stage bio-oxidation process achieved a carbon-nitrogen reduction at 6 days hydraulic retention time (HRT) operating in an extended aeration mode. This paper addresses the studies on selection of a treatment process for removal of organic matter, phenols, cyanide and ammonia nitrogen. The treatment scheme comprising ammonia stripping (pretreatment) followed by the two stage bio-oxidation and chlorination process met the Indian Standards for discharge into Inland Surface Waters. This treatment process package offers a techno-economically viable treatment scheme to neuter hazardous effluent generated from coal carbonization process.
authors.affiliation: Wastewater Technology Division, National Environmental Engineering Research Institute, Council of Scientific & Industrial Research, New Delhi, Nehru Marg, Nagpur 440020, India. p_manekar@neeri.res.in
authors.forename: Pravin
authors.initials: P
authors.lastname: Manekar
authors.forename: Rima
authors.initials: R
authors.lastname: Biswas
authors.forename: Manikavasagam
authors.initials: M
authors.lastname: Karthik
authors.forename: Tapas
authors.initials: T
authors.lastname: Nandy
mesh_terms: D052818:Autotrophic Processes; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism*; D003031:Coal; D003077:Coke; D054879:Halogenation; D006256:Hazardous Waste / Q000331:legislation & jurisprudence / Q000517:prevention & control*; D052836:Heterotrophic Processes; D007194:India; D007220:Industrial Waste / Q000517:prevention & control; D058465:Nitrification; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction
chemical_list: D003031:Coal; D003077:Coke; D006256:Hazardous Waste; D007220:Industrial Waste; D002244:Carbon; D009584:Nitrogen